Esters of polycarboxylic acids and oxypropylated 2, 2&#39;-methylenebis



Patented Jan. 27, 1953 ES-TERS F POLYCARBOXYLIC ACIDS AND OXYPROPYLATED 2,2'-METHYLENEBIS (4- METHYL-6-TERT-BUTYLPHENOL) Melvin De Groote, University City, Mo., assignor to Petrolite Corporation, a corporation of Delaware No Drawing. Application May 14, 1951, Serial No. 226,335

7 Claims.

The present invention is concerned with certain new chemical products, compounds, or compositions which have useful application in various arts. It includes methods or procedures for manufacturing said new chemical products, compounds or compositions, as well as the products, compounds, or compositions themselves.

Complementary to the above aspect of the invention herein disclosed is my companion invention concerned with the use of these particular chemical compounds, or products, as demulsifying agents in processes or procedures particularly adapted for preventing, breaking, or resolving emulsions of the water-in-oil type, and particularly petroleum emulsions. See my co-pending application Serial No. 226,334, filed May 14, 1951.

Said new compositions are fractional esters obtained from a polycarboxy acid and oxypropylated 2,2'-methylenebis (4-methyl-6-tert-butylphenol). Such 2,2'-methylenebis (4-methyl-6-tert-butylphenol) is treated with propylene oxide so the molecular weight, based on the hydroxyl value, is in the range of approximately 1,000 to approximately 5,000. Such oxypropylated derivatives are invariably xylene-soluble and water-insoluble. When the molecular weight, based on the hydroxyl value, is modestly in excess of 1,000, for instance, about 1200 to 1500 and higher, the oxypropylated product is kerosene-soluble. My preference is to use an oxypropylated 2,2'-methylenebis (4-methyl-6-tert-butylphenol) which is kerosene-soluble, as an intermediate for combination with polycarboxy acids, as hereinafter described. Such esterification procedure yields fractional esters which serve for the herein-described purpose.

As is well known, 2,2-methylenebis l-methyl- G-tert-butylphenol) is a chemical compound having the following formula:

. OH OH (011:):0 C(CHs):

' CH: H3

If, for convenience, 2,2-methylenebis (l-methyl-fi tert-butyl-phenol) is indicated thus:

HOR'-OI-I the product obtained by oxypropylation may be indicated thus:

" H(OCaHs)nOR'O(C3HsO)n'H with the proviso that n and n represent whole nunibers, which, added together, equal a sum varying from to 80, and the acidic ester obtained by reaction of the polycarboxy acid may be indicated thus:

in which the characters have their previous significance, and n" is a whole number not over 2 and R is the radical of the polycarboxy acid:

COOH and preferably, free from any radicals having more than 8 uninterrupted carbon atoms in a single group, and with the further proviso that the parent diol, prior to esterification, be preferably kerosene-soluble.

Attention is directed to the co-pending application of C. M. Blair, Jr., Serial No. 70,811, filed January 13, 1949 (now Patent 2,562,878, granted August 7, 1951) in which there is described, among other things, a process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of an esterification product of a dicarboxylic acid and a polyalkylene glycol, in which the ratio of equivalents of polybasic acid to equivalents of polyalkylene glycol is in the range of 0.5 to 2.0, in which the alkylene group has from 2 to 3 carbon atoms, and in which the molecular weight of the product is between 1,500 to 4,000.

Similarly, there have been used esters of dicarboxy acids and polypropylene glycols, in which 2 moles of the dicarboxy acid ester have been reacted with one mole of a polypropylene glycol having a molecular weight, for example, of 2,000 so as to form an acidic fractional ester. Subsequent examination of what is said herein, in comparison with the previous example as well as the hereto appended claims, will show the line of delineation between such somewhat comparable compounds. Of greater significance, however, is what is said subsequently in regard to the structure of the parent diol, as compared to polypropylene glycols whose molecular weights may vary from 1,000 to 2,000.

In the instant application the initial starting material, i. e., 2,2-methylenebis (4-methyl-6- tert-butyl-phenol), is water-insoluble. Numerous water-insoluble compounds susceptible to oxyalkylation, and particularly to oxyethylation, have been oxyethylated so as to produce effective surface-active agents, which, in some instances at least, also have had at least modest demulsitying property. Reference is made to similar monomeric compounds having a hydrophobe group containing, for example, 8 to 32 carbon atoms and a reactive hydrogen atom, such as the usual acids, alcohols, alkylated phenols, amines, amides, etc. In such instances, invariably the approach was to introduce a counterbalancing efiect by means of the addition of a hydrophile group, particularly ethylene oxide, or, in some instances, glycide, or perhaps a mixture of both hydrophile groups and hydrophobe soluble material water-insoluble.

groups, as, for example, in theintroduction of propylene oxide along with ethylene oxide.

Obviously, thousands and thousands of combinations, starting with hundreds of initial waterinsolublematerials, are possible. Exploration of a large number of raw materials has yielded only a few whichappear to be commercially practical and competitive with available demulsifying agents. 2,'2-methylenebis (4-methyl 6 tertbutylphenol) happens to be one such compound. On the other hand, a somewhat closely comparable compound, p-p-bisphenol having the following structure:

does not seem to yield analogous derivatives of nearly the effectiveness of 2,2'-methylenebis (4- methyl-G-tert-butylphenol). This is not only true in regard to p-p'-bisphenol, but also is true in regard to alkylated bisphenol having either one or two alkyl groups with not over 4 carbon atoms present in the alkyl groups. The reason or reasons for this difierence is merely a matter of speculation.

Exhaustive oxypropylation renders a water- Similarly, it renders a kerosene-insoluble material kerosenesoluble; for instance, reference has been made to the fact that this is true, for example, using polypropylene glycol 2,000. Actually, it is true with polypropylene glycol having lower molecular weights than 2,000. These materials are obtained by the oxypropylation of a water-soluble kerosene-insoluble material, i. e., either water or propylene glycol. Just why certain difierent materials which are water-insoluble to start with, and which presumably are rendered more water-insoluble by exhaustive oxypropylation (if such expression more water-insoluble has significance), can be converted into a valuable surface-active agent, and particularly a valuable demulsifying agent, by reaction with a polycarboxy acid which does ,not particularly affect the solubility one way or the other-depending upon the selection of the acid-is unexplainable.

Although the herein described products have a number of industrial applications, they are of particular value for resolving petroleum emulsions of the water-in-oil type that are commonly referred to as cut oil, roily oil, emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in 'a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion. This specific application i described and claimed in my co-pending application Serial No. 226,334, filed May 14, 1951.

The new products are useful as wetting, detergent and leveling agents in the laundry, textile and dyeing industries; as wetting agents and detergents in the acid washing of .building stone :and brick; as wetting agents and spreaders in the application of asphalt in road building and the like; as a flotation reagent in the flotation Part 1 is concerned with the oxypropylation derivatives of 2,2'-methylenebis (4-methyl-6- tert-butylphenol) Part 2 is concerned with the preparation of esters from the aforementioned diols or dihydroxylated compounds; and

Part 3 is concerned with certain derivatives which can be obtained from the diols of the type aforementioned.

PART 1 For a number of well known reasons equipment, whether laboratory size, semi-pilot plant size, pilot plant size, or large scale size, is not, as a rule, designed for a particular alkylene oxide. Invariably, and inevitably, however, or particularly in the case of laboratory equipment and pilot plant size, the design is such as to use any of the customarily available alkylene oxides, i. e., ethylene oxide, propylene oxide, butylene oxide, glycide, epichlorohydrin, styrene oxide, etc. In the subsequent description of the equipment it becomes obvious that it is adapted for oxyethylation as well as oxypropylation.

Oxypropylations are conducted under a wide variety of conditions, not only in regard to presence or absence of catalyst, and the kind of catalyst, but also in regard to the time of reaction, temperature of reaction, speed of reaction, pressure during reaction, etc. For instance, oxyalkylations can be conducted at temperatures up to approximately 200 C. with pressures in about the same range up to about 200 pounds per square inch. They can be conducted also at temperatures approximating the boiling point of water or slightly above, as, for example, to C. Under such circumstances, the pressure will be less than 30 pounds per square inch, unless some special procedure is employed, as is sometimes the case, to wit, keeping an atmosphere of inert gas such as nitrogen in the vessel during the reaction. Such low-temperature-low-reaction rate oxypropylations have been described very com-. pletely in U. S. Patent No. 2,448,664, to H. R. Fife et al., dated September 7, 1948. Low-temperature-low-pressure oxypropylations are particularly desirable where the compound being subjected to oxypropylation contains one, two, or three points of reaction only, such as monohydric alcohols, glycols and triols.

Since low-pressure-low-temperature-low-reaction-speed oxypropylations require considerable time, for instance, 1 to 7 days of 24 hours each to complete the reaction, they are conducted, as a rule, whether on a laboratory scale, pilot plant scale, orlarge scale, so as to operate automatically. The prior figure of seven days applies especially to large-scale operations. I have used conventional equipment with two added automatic features: 1

(a) A solenoid-controlled valve which shuts off the propylene oxide in event that the temperature gets outside a predetermined and set range, for instance, 95 to 120 C.; and

(b) Another solenoid valve which shuts off the propylene oxide (or for that matter ethylene oxide if it is being used) if the pressure gets beyond a predetermined range, such as 25 to 35 pounds. Otherwise, the equipment is substantially the same as is commonly employed for this purpose where the pressure of reaction is higher, speed of reaction is higher, and time of reaction is much shorter. In such instances such automatic controls are not necessarily used.

Thus, in preparing the various examples, I

have found it particularly advantageous to use laboratory equipment or pilot plant which is designed to permit continuous oxyalkylation, whether it be oxypropylation or oxyethylation. With certain obvious changes, the equipment can be used also to permit oxyalkylation involving the use of glycide where no pressure is involved, except the vapor pressure of a solvent, if any, which may have been used as a diluent.

As previously pointed out, the method of using propylene oxide is the same as ethylene oxide. This point is emphasized only for the reason that the apparatus is so designed and constructed as to use either oxide.

The oxypropylation procedure employed in the preparation of the oxyalkylated derivatives has been uniformly the same, particularly in light of the fact that a continuous automatically-controlled procedure was employed. In this procedure the autoclave was a conventional autoclave made of stainless steel and having a capacity of approximately gallons and a working pressure of one thousand pounds gauge pressure. This pressure obviously is far beyond any requirement, as far as propylene oxide goes, unless there is a reaction of explosive violence involved due to accident. The autoclave was equipped with the conventional devices and openings, such as the variable-speed stirrer operating at speeds from 50 R. P. M. to 500 R. P. M.; thermometer well and thermocouple for mechanical thermometer; emptying outlet; pressure gauge, manual vent line; charge hole for initial reactants; at least one connection for introducing the alkylene oxide, such as propylene oxide or ethylene oxide, to the bottom of the autoclave; along with suitable devices for both cooling and heating the autoclave, such as a cooling jacket, and preferably, coils in addition thereto, with the jacket so arranged that it is suitable for heating with steam or cooling with water and further equipped with electrical heating devices. Such autoclaves are, of course, in essence, small-scale replicas of the usual conventional autoclave used in oxyalkylation procedures. In some instances, in ex-- ploratory preparations an autoclave having a smaller capacity, for instance, approximately 3 liters in one case, and about 1% gallons in another case, was used. 1

Continuous operation, or substantially continuous operation, was achieved by the use of a separate container to hold the alkylene oxide being employed, particularly propylene oxide. In conjunction with the smaller autoclaves, the container consists essentially of a laboratory bomb having a capacity of about one-half gallon, or somewhat in excess thereof. In some instances, a larger bomb was used, to wit, one having a capacity ofabout one gallon. This bomb was equipped, also, with an inlet for charging, and an eductor tube going to the bottom of the container so as to permit discharging of alkylene oxide in the liquid phase to the autoclave. A bomb having a capacity of about 60 pounds was used in connection with the 15-gallon autoclave. Other conventional equipment consists, of course,

' of the rupture disc, pressure gauge, sight feed glass, thermometer, connection for nitrogen for pressuring bomb, etc. The bomb was placed on a scale during use. The connections between the bomb and the autoclave were flexible stainless steel hose or tubing so that continuous weighings could be made without breaking or making any connections. This applies also to the nitrogen line, which was used to pressure the bomb reservoir. To the extent that it was required, any other usual conventional procedure or addition which provided greater safety was used, of course, such as safety glass protective screens, etc.

Attention is directed again to what has been said previously in regard to automatic controls, which shut off the propylene oxide in event temperature of reaction passes out of the predetermined range, or if pressure in the autoclave passes out of predetermined range.

With this particular arrangement practically all oxypropylations become uniform, in that the reaction temperature was held within a few degrees of any selected point, for instance, if C. was selected as the operating temperature the maximum point would be at the most C. or 112 C., and the lower point would be 95, or possibly 98 C. Similarly, the pressure was held at approximately 30 pounds within a 5- pound variation one way or the other, but might drop to practically zero, especially where no solvent such as xylene is employed. The speed of reaction was comparatively slow under such conditions as compared with oxyalkylations at 200 C. Numerous reactions were conducted in which the time varied from one day (24 hours) up to three days (72 hours), for completion of the final member of a series. In some instances, the reaction may take place in considerably less time, i. e., 24 hours or less, as far as a partial oxypropylation is concerned. The minimum time recorded was about a 2 /2-hour period in a single step. Reactions indicated as being complete in 10 hours may have been complete in a lesser period of time in light of the automatic equipment employed. This applies also where the reactions were complete in a shorter period of time, for instance, 4 to 5 hours. In the addition of propylene oxide, in the autoclave equipment as far as possible the valves were set so all the propylene oxide, if fed continuously, would be added at a rate so that the predetermined amount would react within the first 15 hours of the 24-hour period or two-thirds of any shorter period. This meant that if the reaction was interrupted automatically for a period of time for pressure to drop or temperature to drop, the predetermined amount of oxide would still be added, in most instances, well within the predetermined time period. Sometimes where the additionwas a comparatively small amount in a 10-hour period, there would be an unquestionable speeding up of the reaction, by simply repeating the examples and using 2, 3, or 4 hours instead of 5 hours.

When operating at a comparatively high temperature, for instance, between 150 to 200 C., an unreacted alkylene oxide such as propylene oxide, makes its presence felt in the increase in pressure, or the consistency of a higher pressure. However, at a low enough temperature it may happen that the propylene oxide goes in as a liquid. If so, and if it remains unreacted, there is, of course, an inherent danger and appropriate steps must be taken to safeguard against this possibility; if need be, a sample must be withdrawn and examined for unreacted propylene oxide. One obvious procedure, of course, is to oxypropylate at a modestly higher temperature, for instance, at to C. Unreacted oxide affects determination of the acetyl or hydroxyl value of the hydroxylated compound obtained.

The higher the molecular weight of the compound, i. e., towards the latter stages of reaction, the longer "the time required"'to' adda givem amount of oxide. One possible explanation is that the molecule, being larger, theopportunity for random reaction is decreased. Inversely, the lower the molecular weight, the faster the reaction takes place. For this reason, sometimes at least, increasing the concentration of the catalyst does not appreciably speed up the reaction, particularly when the product subjected to oxyalkylation has a comparatively high molecular weight. However, as has been-pointed-out=previously, operatingnat a low pressure and a low temperature even in large scale operations as much'as' a week orten days time may elapse to obtain some of the" higher molecular weight derivatives from monohydricor dihydric materials.

Ina number of 'operation-sthe' counter-balance scale or-ridial-scale holding the propylene oxide bomb was so set" that whenthe predetermined amount of propylene oxide had passed into-Ithe reaction, thescale movement through'atimeoptcrating device was set for either one to twehours, so that reaction continued j-for l'to =3 hours after the .finaliaddi-tion of the last'propylene oxide, and thereafter th'e o'peration was-shut down. This particular, device is particularlysuitable for use enlargerequipment:.than laboratory size "auto-'- claves, towit, on semi-pilot plant or pilot plant size; as well as on large scale size. This final stirring period is intended *to avoid the presence otunreacted oxide.

In this: sort of operation, of course; the tent; peratureirange was controlled automatically by either use of cooling water, steam, or'electrical heat, so as to raise or lower "the temperature. The pressuring of the propylene-oxide into the reaction 'vessel was also'automatic insofar that thee-feed stream was set for a slow-, continuous run which was shut off in case the pressure passed a" predetermined point, as previously -set out. Allg the points of design, construction, etc, were conventional including the gaugess-check valves and entire equipment. awareat least two firms, and possibly three, s'pe' cialize in autoclave equipment such-as I have em..- ployed in the laboratory, and are' pre'pared to furnish-equipment of this same kin-d. Similarly,

pilot plant equipment is available. This point-is simply made as a precaution in the direction of safety. xyallrylations, particularly involving ethylene oxide,- glycide, propylene oxide; etc," should not be conducted except in equipment specifically designed for the purpose.

Example 1a The starting material was a commercial-grade of'i2,2"-methylenebis (4-methyl-fi tert-butylphes 11-01). The particular autoclave employed was one having a capacity of about 15 gallons or ori the average of 125 pounds of reaction mass. The

speed 'of the stirrer could be varied from about 150 to 350 R. P. M. Approximately pounds of As far as :'-I am i the stirring was continued foranotherone+hal hour. The pressuring device was set foryamaxix, mum of 35 to 37'. pounds per square inch.- This. meant that the bulk of the reaction could take place, and probably did take place, at a lower pressure.- The comparatively low.pressuze-*-w' S.-

Example 2a 54.25 pounds of the reaction mass-identified as. Example 1a., preceding, .and equivalent ,fto. .!,l6-j pounds of the original aromaticreactant,38.37 pounds of propylene oxide, .87 pound oticaus tic soda, and 6.35 pounds of xylene, were to remain in the reaction-vessel. Without'the addition of any more catalyst, 44 pounds of pro: pylene oxide were added. The ox nb ropylatiol' 1- was conducted in substantially the same manner in regard to pressure and temperature as in :EX! ample 1a, preceding,v except i that thereaction time was slightly longer, i. e.. 4-hours,insteado 3 hours. At the end of the reactiongperiqd h lit of the reaction mass was withdrawn a ml ployed as a sample and oxypi nvlation c031: tinned with the remainder of'the reactibnzmass.-. as described in Example 3a, following.

Example 3a..

subjected to further oxypropylation, -as described in Example 4a, following."

Example 4a 67.50 pounds ot'the reaction mass identified Example 3a, preceding, and equivalen 0" f pounds of the aromatic reactantz wififi "pounds-of propylene'oxide, .42 pound of caustic soda,,an.d

3.03 pounds of xylene, were permitted to, remiiih I,

in the autoclave. Without adding anal-more cote alyst, this reaction mass was subjected to further oxypropylation in the same manner as inthe pre ceding examples. 21 pounds of propylene oxide were added in a 3 hour period. Conditions. as

faras temperature and pressure were concernedwere the'same as in preceding examples.

In this particular series of examples the'oxv-- propylation was stopped at this stage Infother series I have continued the oxypropylationikso oxide treating 2,2'-methyle'nebis (4-methyl-6-tert-butylphenol) with 1 to 10 moles of butylene oxide, ethylene oxide, or ,a mixture of the two, can then be subjected to oxypropylation in the same manner as illustrated by previous examples so as, to yield products having the same molecular weight characteristics and the same solubility or 'emulsifiability in kerosene. H

What is said herein is presented in tabular form in Table 1, immediately following, with some added information as to molecularweight and as to solubility of the reaction product in water, xylene, and kerosene.

In the above formulas the large X is obviously not intended to signify anything except the central part of a large molecule, whereas, as faras a speculative explanation is concerned, one need only consider the terminal radicals, as shown. Such suggestion is of interest only, because it may be a possible explanation of how an increase in hydroxyl value does take place which could be interpreted as a decrease in molecular weight. This matter is considered subsequently in the final paragraphs of the next part, i. e., Part 2.

The final products at the end of the oxypropylation step, were somewhat viscous liquids, more viscous than ordinary polypropylene glycols, with a dark amber tint. This color, of course, could be removed, if desired, by means of bleaching clays, filtering chars, or the like.

TABLE 1 Composition Before Composition at End Ex. V Theo. Time, No. Oxide Cata- S01 M. W. E Oxide Oata- Hyd. Max. hrs. 4 M I 4 vent 4 M Pres. (H31, Amt, lyst, Amt Amt, lyst, Mol. Temp 1b 1 lbs. lbs lbs 1m lbs. lbs. Wt. r. sq f la"... 10. O 1. O 7. l, 830 10. O 43. 75 1. 0 960 240-250 37. 37 3 2a 8. 76 38. 27 87 6. 3, 585 8. 76 82. 27 87 1, 842 240-250 37. 37 4 3a... 4. 67 43. 73 47 3. 38 5, 170 4. 67 66. 73 47 2, 170 240-250 37. 37 2% 4a..." 4. 20 59. 85 42 3. 03 6. 890 4. 2O 80. 85 42 2, 250 240250 37. 37 3% Examples la through 4a, inclusive, were all insoluble in water, soluble in xylene and soluble in kerosene.

Ordinarily in the initial oxypropylation of a simple compound such as ethylene glycol or propylene glycol, the hydroxyl molecular weight is apt to approximate the theoretical molecular weight, based on completeness of reaction, if oxypropylation is conducted slowly and at a comparatively low temperature, as described. In

this instance, however, this does not seem to follow, as it is noted in the preceding table that at the point where the theoretical molecular weight is approximately 2,000, the hydroxyl molecular weight is only about one-half this amount; This generalization does not neces sarily apply where there are more hydroxyls present, and in the present instance the results are somewhat peculiar when compared with simple dihydroxylated materials, as described, or with phenols.

The fact that such pronounced variation take place between hydroxyl molecular weight and theoretical molecular weight, based on completeness of reaction, has been subjected to examination and speculation, but no satisfactory rational has been suggested. When a nitrogencontaining compound is present, such as in the oxypropylation of acetamide or polyamine, the situation becomes even more confused.

One suggestion has been that one hydroxyl is lost by dehydration, and that this ultimately causes a break in the molecule in such a way that two new hydroxyls are formed. Thisis shown after a fashion in a highly idealized manner in the following way:

CH3 OH:

35 sion of propylene oxide into the desired hydroxylated compounds. This is indicated by the fact that the theoretical molecular weight, based on a statistical average; is greater than the molecular weight calculated by usual methods, on basis of acetyl or hydroxyl value. This is true even in the case of a normal run of the kind noted previously.

Actually, there is no completely satisfactory method for determining molecular weights of these types of compounds with a high degree of accuracy when the molecular weights exceed 2,000. In some instances, the acetyl value or hydroxyl value serves as satisfactorily as an index' to the molecular Weight as any other procedure, subject to the above limitations, and especially in the higher molecular weight range. If any difliculty is encountered in the manufacture of the esters, as described in Part 2, the stoichiometrical amount of acid or acid compound should be taken which corresponds to the indicated acetyl or hydroxyl value. This matter has been discussed in the literature and is a matter of common knowledge and requiresno further elaboration. In fact, it is illustrated by some of the examples appearing in the patent previously mentioned.

PART 2 As previously pointed out, the present inven tion is concerned with acidic esters obtained from the oxypropylated derivatives described in Part 1, immediately preceding, and polycarboxy acids, particularly tricarboxy acids like citric and dicarboxy acids such as adipic acid, phthalic acid, or anhydride, succinic acid, diglycollic acid, sebacic acid, azelaicacid, aconitic acid, maleic' acid or anhydride, citraconic acid or anhydride; maleic acid or anhydride adducts, as obtained by the Diels-Alder reaction from productssuch as maleic anhydride, and cyclopentadiene. Such acids should be heat-stable so they are not decomposed during esterification. They may contain as many as 36 carbon atoms, as, for example, the acids obtained by dimerization of unsaturated fatty acids, unsaturated monocarboxy fatty acids, or unsaturated monocarboxy acids having 18 carbon atoms. Reference to the acid in the hereto appended claims obviously includes the anhydrides or any other obvious equivalents. My pref erence, however, is to use polycarboxy acids having not over 8 carbon atoms.

The production of esters including acid esters (fractional esters) from polycarboxy acids and glycols or other hydroxylated compounds is well known. Needless to say, various compounds may be used such as the low molal ester, the anhydride, the acyl chloride, etc. However, for purpose of economy, it is customary to use either the acid or the anhydride. A conventional procedure is employed. On a laboratory scale one can employ a resin pot of the kind described in U. S. Patent No. 2,499,370, dated March 7, 1950, to De Groote & Keiser, and particularly with one more opening to permit the use of a porous spreader, if hydrochloric acid gas is to be used as a catalyst. Such device or absorption spreader consists of minute alundum thimbles which are connected to a gas tube. One can add a sulfonic acid such as paratoluene sulfonic acid as a catalyst. There is some objection to this, because in some instances, there is some evidence that this acid catalyst tends to decompose or rearrange the oxypropylated compounds, and particularly likely to do so if the esterification temperature is too high. In the case of polycarboxy acids such as diglycollic acid, which is strongly acidic, there is no need to add any catalyst. The use of hydrochloric acid gas has one advantage over para-toluene sulfonic acid, and that is, that at the end of the reaction, it can be removed by flushing out with nitrogen, Whereas, there is no reasonably convenient means available of removing the para-toluene sulfonic acid or other sulfonic acid employed. If hydrochloric acid is employed, one need only pass the gas through at an exceedingly slow rate so as to keep the reaction mass acidic. Only a trace of acid need be present. I have employed hydrochloric acid gas or the aqueous acid itself to eliminate the initial basic material. My preference, however, is to use no catalyst whatsoever and to insure complete dryness of the diol, as described in the final procedure just preceding the Table II.

The products obtained in Part 1, preceding, may contain a basic catalyst. As a general procedure, I have added an amount of half-concen trated hydrochloric acid considerably in excess of what is required to neutralize the residual catalyst. The mixture is shaken thoroughly and allowed to stand overnight. It is then filtered and refluxed with the xylene present until the water can be separated in a phase-separating trap. As soon as the product is substantially free from water the distillation stops. This preliminary step can be carried out in the flask to be used for esterification. If there is any further deposition of sodium chloride during the reflux stage, needless to say, a second filtration may be required. In any event, the neutral or slightly acidic solution of the oxypropylated derivatives described in Part 1 is then diluted further with suflicient xylene, decalin, petroleum solvent, or the like, so that one has obtained approximately a 45% solution. To this solution there is added a polycarboxylated reactant, as previously described, such as phthalic anhydride, succinic acid, or anhydride, diglycollic acid, etc. The mixture is refluxed until esterification is complete, as indicated by elimination of water or drop in carboxyl value. Needless to say, if one produces a half ester from an anhydride such as phthalic anhydride, no water is eliminated. However, if it is obtained from diglycollic acid, for example, water is eliminated. All such procedures are conventional and have been so thoroughly described in the literature that further consideration will be limited to a few examples and a comprehensive table.

Other procedures for eliminating the basic residual catalyst, if any, can be employed. For example, the oxyalkyl-ation can be conducted in absence of a solvent or the solvent removed after oxypropylation. Such oxypropylation end product can then be acidified with just enough concentrated hydrochloric acid to just neutralize the residual basic catalyst. To this product one can then add a small amount of anhydrous sodium sulfate (suflicient in quantity to take up any water that is present) and then subject the mass to centrifugal force so as to eliminate the hydrated sodium sulfate and probably the sodium chloride formed. The clear, somewhat viscous,.

quite dark amber liquid so obtained may contain a small amount of sodium sulfate or sodium chloride, but in any event, is perfectly acceptable for esterification in the manner described.

It is to be pointed out that the products here described are not polyesters in the sense that there is a plurality of both diol radicals and acid radicals; the product is characterized by having only one diol radical.

In some instances, and in fact, in many instances, I have found that in spite of the dehydration methods employed above, a mere trace of water still comes through, and that this mere trace of water certainly interferes with the acetyl or hydroxyl value determination, at least when a number of conventional procedures are used and may retard esterification, particularly where there is no sulfonic acid or hydrochloric acid present as a catalyst. Therefore, I have preferred to use the following procedure: I have employed about 200 grams of the diol compound, as described in Part 1, preceding; I have added about 60 grams of benzene, and then refluxed this mixture in the glass resin pot, using a phase-separat ing trap until the benzene carried out all the water present as water of solution or the equivalent. Ordinarily this refluxing temperature is apt to be in the neighborhood of to possibly C'. When all this water or moisture has been removed, I also withdraw approximately 20 grams or a little less benzene and then add the required amount of the carboxy reactant and also about 150 grams of a high boiling aromatic petroleum solvent. These solvents are sold by various oil refineries, and, as far as solvent effect, act as if they were almost completely aromatic in character. Typical distillation data in the particular type I have employed and found very satisfactory is the following:

I. B. P., 142 C. 30 ml., 225 C. 5 ml., 200 C. 35 ml., 230 C. 10 m1., 209 C. 40 ml., 234 C. 15 m1., 215 C. 45 ml., 237 C. 20 m1., 216 C. 50 mL, 242 C. 25 ml.. 220 C. 55 1111., 244 C.

to 1111., 7548 6. so m1., 264 4-353? .1- 85 1111-; 37? Q 1111., 13525; 0..., 9011111110 0. 1111,2611 c M 1111,307 c.

Alter this teridl is ,added, refluxing is comtixi'ud, ah 6f colirse; is at a high temperature, @1711, (ab t,"'160f. 1b*170 0., If the ca'rboxyret is en enhydiide, needless to say, no water f 111 11119 1 ebbeers; i'tthe cerboxyreactaht is an ter of reactioh should appear and shou'ld 1 11111111111111 at the above reaction temperature.

. 14 If the solvent 15' to be removed by distinetion', efti'd particularly, vacuum dlstiliation, then the high boiling aromatic petroleurn solvent might well bie'pleced by soifie more expensive solvent,

5 such as decaiizi of an elkylated deeaIin which has arathejr definite or close range boiling point. The lie-111011911 of the solvent, of course, is purely a conventional pf-ocedfire and requires no elaboration. 1 1 In the case of a compound inherently aromatic and havinge comparatively 16w oxygen content, such as 2,2' fi1ethylenebis 4-me1hy1-e-tertbutylpheno l), I haveiound that xylene by itself is fijractically as satisfactory :as anything else, althoti'gh aromatic solvents, mixedarornatic s01- vents, endthellike, may be employed, if desired. I have found decalin to be very suitable. ,In the subseqlient examples xylene was used exelusively, but my ohe 0f the other solvents indicated may be used just as satisfactorily.

Tables 2 and 3, are self-explanatory and very complete, and it is believed he further elaboration is necessary.

TABLE 2 1 Ex. Theo. Amt. Atht. of Ex. No No. fi fi y- Agual oi Poly- 01.40111 of: a droxy] (h0g1 31 Hyd. Polyear'boxy Reactant earboiy Ester Hyd. H C -V. of Value Actual Cmpd. Reaetant Gmpd H. C. H V (grs.) (grs.)

1a 1, s30 61. a 117 960 184 mglycolne Acid 51. 5 111 1,830 61.3 117 960 189 Aeoqitic Acid 68.5 111. 1, 830 61. 3 117 960 185 Oszilrc Acid; 48. 5 111 1,830 611 3 117 960 182 M a1e1c gAnlhydridm 37. 2 1a 1,830 61.3 1 117 960 184 C1traeor1ie Anhydride. 43. 3 1a 1, 830 61. 8 117 960 184' Phthalid Anhydride"... 57.0 211 a, 585 31. 2 60.9 1, 842 192 Di lyepnie Acid 27.8 211 3, 585 31.2 60. 9 1; 842 197 Aeon 1t1c 401d. 37. 2 2a 3, 585 31. 2 s0. 9 1, 842 191 oxeh Am .1 26. 2 2a 3, 585 31. 2 60. Q 1, 842 196 Melee .etnhydride, 20.8 211 3, 586 31. 2 60. 9 1, 842 193 Cittacohie Anhydride.. 23.6 2a 3, 585 31. 2 60. 9 1, 842 197 Phthalic Anhydride..." 31.6 3;: 5, 170 21. 7 51. 11 2, 170 202 ni ly eiiieheid 25. 0 3a 5, 170 21. 7 51. 6 2, 170 202 Oxahe Ae1d 23. 4 3a 5, 1.70 21. 7 51. 6 2, 170 209 Aconitm A c1d' 33. 6 3a 5, 170 21. 7 51. 6 2. 170 202 M21914 A nhydnd 18. 7 3a 6, 170 21. 7 51. 6 2, 170 204 Cltracomc Anhydri 21.0 3a 5, 170 21. 7 51. 6 2, 170 204 Pl lthalic Anhydride... 27. 8 4a 6, 890, 10. 4 49. 8 2 250 204 Dmye lie: '(1 24. 3 411 6, 890 16. 4 49. 8 2, 250 200 Phthalie Anhydride 26. 4 4a 6, 890 16. 4 49. 8 2, 250 203 Aeonitic Acid 31. 2 4a 6, 890 16. 4 49. 8 250 206 0x311? Acid. 23. 1 4a 6, s90 16. 4 49.8 2, 250 204 M lee, Anhydrid 17.8 411 B, 890 16. 4 49. 8 2. 250 200 Oitraconie Aziyhdri 19. 9

TABLE 3 Amt. Maximum 21 313- 801... 3;; E2522; ,3 3

Ester (gm) no G tlon (hrs.)

The data. included in the subsequent tab1es,i.e.,

The procedure for manufacturing the esters has been illustrated by preceding examples. If, for any reason, reaction does not take place in a manner that is acceptable, attention should be directed to the following details:

(a) Recheck the hydroxyl or acetyl value of the oxypropylated 2,2-methylenebis (4-methyl- 6-tert-butylphenol), and use a stoichiometrically equivalent amount of acid;

(b) If the reaction does not proceed with reasonable speed, either raise the temperature indicated or else extend the period of time up to 12 or 16 hours, if need be;

(c) If necessary, use of paratoluene sulfonic acid, or some other acid as a catalyst; and

(d) If the esterification does not produce a clear product, a check should be made to see if an inorganic salt such as sodium chloride or sodium sulfate is not precipitating out. Such salt should be eliminated, at least for exploration experimentation, and can be removed by filtering. Everything else being equal, as the size of the molecule increases and the reactive hydroxyl radical represents a smaller fraction of the entire molecule, more difficulty is involved in obtaining complete esterification.

Even under the most carefully controlled conditions of oxypropylation involving comparatively low temperatures and long time of reaction, there are formed certain compounds whose compositions are still obscure. Such side reaction products can contribute a substantial proportion of the final cogeneric reaction mixture. Various suggestions have been made as to the nature of these compounds, such as being cyclic polymers of propylene oxide, dehydration products with the appearance of a vinyl radical, or isomers of propylene oxide or derivatives thereof, i. e., of an aldehyde, ketone, or allyl alcohol. In some instances, an attempt to react the stoichiometric amount of a polycarboxy acid with the oxypropylated derivative results in an excess of the carboxylated reactant, for the reason that apparently under conditions of reaction less reactive hydroxyl radicals are present than indicated by the hydroxyl value. Under such circumstances, there is simply a residue of the carboxylic reactant which can be removed by filtration, or, if desired, the esterification procedure can be repeated, using an appropriately reduced ratio of carboxylic reactant. I

Even the determination of the hydroxyl value by conventional procedure leaves much to be desired, due either to the cogeneric materials previously referred to, or, for that matter, the presence of any inorganic salts or propylene oxide. Obviously, this oxide should be eliminated.

The solvent employed, if any, can be removed from the finished ester by distillation, and particularly vacuum distillation. The final products or liquids are generally from almost black or reddish black to dark amber in color, and show moderate viscosity. They can be bleached with bleaching clays, filtering chars, and the like. However, for the purpose of demulsification or the like, color is not a factor and decolorization is not justified.

In the above instances I have permitted the solvents to remain present in the final reaction mass. In other instances I have followed the same procedure, using decalin or a mixture of decalin or benzene in the same manner and ultimately removed all the solvents by vacuum distillation. i

15 PART 3 One need not point out the products obtained as intermediates, 1. e., the oxypropylation products, can be subjected to a number of other reactions which change the terminal groups, as, for example, reaction of ethylene oxide, butylene oxide, glycide, epichlorohydrim'etc. Such products still having residual hydroxyl radicals can again be esterified with the same polycarboxy acids described in Part 2 to yield acidic esters, which, in turn, are suitable as demulsifying agents. l

Furthermore, such carboxylated compounds obtained from the polyoxypropylated materials described in Part 1, or for that matter, the very same oxypropylated compounds described in Part 1 without further reaction, can be treated with a number of reactive materials, such as dimethyl sulfate, sulfuric acid, ethylene imine, etc., to yield entirely new compounds. If treated with maleic anhydride, monochloroacetic acid, epichlorohydrin, etc., one can prepare further obvious variants by (a) reacting the maleic acid ester after esterification of the residual carboxyl radical with sodium bisulfite so as to give a sulfosuccinate. Furthermore, derivatives having a labile chloride atom such as those obtained from chloroacetic acid or epichlorohydrin, can be reacted with a tertiary amine to give quaternary ammonium compounds. The acidic esters described herein can, of course, be neutralized with various compounds, so as to alter the water and oil solubility factors, as, for example, by the use of triethanolamine, cyclohexylamine, etc. All these variations and derivatives have utility in various arts where surface-active materials are of value, and particularly are efiective as demulsifiers in the resolution of petroleum emulsions. They may be employed also as break-inducers in the doctor treatment of sour crude, etc.

Having thus described my invention, what I claim as new and desire to secure by Letters Paten 1s:

1. Hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

in which R is the radical of 2,2-methylenebis (4-methyl-G-tert-butylphenol); n and n are numerals with the proviso that n and 12. equal a sum varying from 15 to 80, and n" is a whole number not over 2, and R is the radical of the ptolybasic acid having not more than 8 carbon a oms:

COOH

(COOH),."

in which n" has its previous significance.

2. Hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

in which R. is the radical of 2,2-methy1enebis (4-methyl-G-tert-butylphenol) n and n are numerals with the proviso that n and n equal a sum varying from 15 to 80, and R is the radical 17 18 of the dicarboxy acid having not more than 8 6. The product of claim 2, wherein the dicarcarbon atoms boxy acid is citraconic acid.

000K 7. The product of claim 2, wherein the dicar- R boxy acid is diglycoliic acid.

COOH 5 his said dicarboxy acid having not over 8 carbon MELVIN P GROOTE' atoms. mar

3. The product of claim 2, wherein the dicar- Wltnesses to mark:

W. C. ADAMS boxy acid is phthahc acid.

4. The product of claim 2, wherein the dicar- 10 DE GROOTE' boxy acid is maleic acid. No references cited.

5. The product of claim 2, wherein the dicarboxy acid is succinic acid. 

1. HYDROPHILE SYNTHETIC PRODUCTS; SAID HYDROPHILE SYNTHETIC PRODUCTS BEING CHARACTERIZED BY THE FOLLOWING FORMULA: 